National Weather Service Training
Center

Cooperative Weather
Stations

Typical Cooperative Weather Observing
Station

What is a Cooperative
Weather Station?

Today weather observers who make up the
Cooperative Observing Program are a
core of volunteers numbering over 10,600. There history extends
back long before there was a National Weather Service. Of these,
about 5,000 make up the "climate" network while the remainder of
the network supports hydrology or meteorology. This network of
volunteer weather watchers has become an American institution.
The program and its history of success continue to arouse the
envy of other countries around the globe. It has been acclaimed
as the most cost-effective weather data collection network in the
world.

The all volunteer weather observer network was envisioned by
Thomas Jefferson in 1776 when he began to recruit observers in
Virginia. By 1800, his vision has spread to five other states. By
1891, the network had grown to nearly 2,000. In 1856 the
Honorable Isaac Newton, U.S. Commissioner of Agriculture,
endorsed a recommendation by the Secretary of the Smithsonian
Institution, Prof. Joseph Henry, that a more extensive weather
service be established for the benefit of agriculture. Five years
later the U.S. Weather Bureau became a new agency under the U.S.
Signal Service. On February 2, 1870, President Ulysses S. Grant
signed a joint resolution of Congress authorizing the
establishment of a national weather bureau. With the Organic Act
of October 1, 1890, all weather functions were transferred to a
new agency called the Weather Bureau. Among other duties, one of
the primary mandates of the Organic Act was the volunteer
weather observer program. This program has evolved into the
National Weather Service (NWS) Cooperative Weather Observer
Network. Although the network has been very successful in
fulfilling its original agriculturally oriented mission of
defining the weather and climate of the United States, its data
are now used for a myriad of things including water and land
management, recreation, environmental impact studies, litigation
and insurance, energy production and energy use, engineering,
architectural design and construction, and agriculture and farm
management, to mention a few. Not only are the Cooperative
Weather data invaluable to the NWS, but these data are also the
basis for critical business decisions in the private sector.
Without these data, the National Weather Service would find it
nearly impossible to fulfil its mission.

Today, the Cooperative Observer Network operates basically as it
did the first year of its inception over 100 years ago.
Cooperative Weather Stations, scattered over all 50 states,
Puerto Rico, and the Virgin Islands, are taking weather
observations seven days a week throughout the year. The
Cooperative Weather Observers provide a myriad of vital
information for their local areas.

It is estimated that the Cooperative Weather Observers donate
their time to the tune of over a million hours a year, netting
the public more per dollar expended than any other government
service in the world. Their data become more valuable with time.
Their data form the cornerstone of the Nation's climatological
history.

Cooperative Weather Observers come from all walks of life.
Farmers, teachers, lawyers, doctors, housewives, and retirees are
all among those individuals contributing to the program.
Individual observers are usually long-time local residents of the
area. This provides longevity and continuity of data. In addition
to private citizens, many local, state, and federal government
offices actively participate in the program. Power plants, water
and pollution control plants, schools and universities, and
members of the media also provide Cooperative Weather
observations. Observers are recruited in predetermined locations
to fill a specific data need. This need may be to define the
climate of an area, to obtain data for NWS hydrologic operations,
augment data from the Automated Surface Observing System (ASOS),
or provide credible ground truth data.

Equipment

Type of weather data recorded at the 10,600 Cooperative Weather
Stations varies as does the equipment they use. The NWS provides
the instruments, frequent visits, equipment maintenance and
observer training to all Cooperative Weather Observers.

Precipitation

Standard 8-inch Rain Gage (Left). The funnel (normally located at
the top of the gage) and measuring tube (normally inside the case
below the funnel) are on the ground at the base of the gage.
Fischer-Porter Recording Rain Gage (Right).

Most weather stations are equipped with the Standard 8-inch
Rain Gage (pictured above on the left) to record daily
precipitation. Others sites have recording rain gages such as the
Fischer-Porter (pictured above on the right) to record rainfall
amount as a function of time. Recording rain gage data make up
the primary data input necessary for production of the Hourly
Precipitation Data publication produced by
NCDC.

Temperature

Cotton Region Shelter

Station that take temperature observations use either the Cotton
Region Shelter (pictured above) or Maximum/Minimum Temperature
Systems (MMTS) (pictured below). The Cotton Region Shelter
provides a shaded, well-ventilated area for maximum and minimum
thermometers used to acquire daily temperature extremes. The MMTS
electronically measures and memorizes the daily maximum and
minimum temperatures. Daily highs and lows are recorded on forms
which are processed by the National Climatic Data Center in
Asheville, NC. Still other stations record a myriad of weather
and climatic data use by both government and private user.

Maximum-Minimun Temperature System
(foreground)

Evaporation

Some Stations have evaporation equipment to document moisture
evaporation data used in both hydrology and agriculture.

Evaporation pan and associated
equipment.

River
Equipment

Many observers take river and stream level reading to support the
NWS hydrology forecast and warning programs. Water levels are
measured using either a Staff Gage or a Wire Weight River Gage
(shown at the left). The
installation of a wire weight
gage is described on another web page at this site.

Disposition of
Data

At official NWS Cooperative Weather Stations observations are
taken from instrumentation provided and maintained by the
National Weather Service. Observations are taken at least once a
day. Some stations provide data more often than others.
Observations are recorded from instrument readings obtained at
predetermined times to form a consistent weather picture that has
occurred in the local area for a specific period, usually 24
hours. These recorded weather reports are documented on NWS forms
and mailed by the observer to the NWS who forwards them to the National Climatic Data
Center (NCDC) for processing. The Cooperative Weather
Observer's data are also becoming more critical to operational
decision made at the NWS office. With this fact in mind, the NWS
is now in the midst of a program of near real time data
acquisition known as Remote Observation System Automation or
ROSA. When fully implemented, all data elements from
Cooperative Weather Stations throughout the Nation will be
electronically transmitted directly to the NWS where data will be
ingested into forecasting models after appropriate quality
control is applied to these data.